The association of new-onset diabetes mellitus and medical therapy for benign prostatic hyperplasia: A population-based study

Abstract

Introduction: Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms are highly prevalent in the aging male. Similarly, the prevalence of metabolic syndrome is increasing worldwide, with mounting evidence that these two common conditions share more than age as a predisposing factor. The objective of this study was to determine if medical management of BPH is associated with an increased risk of new-onset diabetes mellitus (DM) in routine care. Methods: This population-based, retrospective cohort study expands on a parent study of linked administrative databases identifying patients diagnosed and treated for BPH between 2005 and 2015. The primary outcome of this secondary analysis was a new diagnosis of DM after the index date of BPH diagnosis. Covariates included age, dyslipidemia, hypertension, and vascular diseases. A Cox proportional hazards regression model was used for inferential statistical analysis. Results: A total 129 223 men were identified with a BPH diagnosis and no prior history of DM. Of those men, 6390 (5%) were exposed to 5-alpha-reductase inhibitor (5-ARI), 39 592 (31%) exposed to alpha-blocker (AB), and 30 545 (24%) exposed to combination therapy. Compared to those men with no BPH medication use, those exposed to drugs had an increased risk of new DM. Men treated with combination therapy of 5-ARI and AB (hazard ratio [HR] 1.30, 95% confidence interval [CI] 1.25–1.35), 5-ARI monotherapy (HR 1.25, 95% CI 1.17–1.34), or AB monotherapy (HR 1.17, 95% CI 1.13–1.22) all were at higher risk of new DM diagnosis after adjusting for important covariates. When calculating the risk of a new diabetes diagnosis measured from the start of drug exposure, men treated with 5-ARIs had an increased risk of DM compared to AB monotherapy as the reference, with HR 1.12 (95% CI 1.03–1.21) for 5-ARI monotherapy and HR 1.20 (95% CI 1.14–1.25) for combination therapy. Conclusions: In this large, long-term, retrospective study of men with a BPH diagnosis in routine practice, the risk of a new diagnosis of DM was greater in patients receiving medical management compared to controls. This modest but significant increased risk was highest in men treated with any 5-ARIs, in combination as well as monotherapy, compared to the ABs.